When Cuomo unveiled his first budget, the union-backed Alliance for Quality Education released a video featuring its spokesperson—a familiar, telegenic woman standing in a home kitchen. “New York State has a budget to balance, and Governor Cuomo thinks the way to do it is by slashing New York’s public schools,” she said, throwing school supplies into a trashcan to underscore her point.

Eight years later, Cynthia Nixon is still attacking Cuomo’s education policies—but as a competing Democratic candidate for governor. “New York’s schools are the second most unequal in the entire country,” Nixon, the former Sex and the City star, said in her kickoff speech in March, “and the gap between the richest and the poorest schools has grown wider today, under Andrew Cuomo, than it’s ever been.”

Nixon’s criticism of Cuomo has remained constant, but the politics of education have not—in ways that should work in her favor, theoretically. Not long ago, many prominent Democrats—including President Barack Obama—supported charter schools and other centrist education policies, such as linking teacher evaluations to standardized test scores. But President Donald Trump’s choice of Betsy DeVos, a longtime advocate of school privatization, as his education secretary has made charters—and anything remotely resembling “school choice”—increasingly toxic for Democrats.

“What’s really interesting is how fast the Obama-era reforms have been buried in the basement,” said Rick Hess, a scholar at the American Enterprise Institute, who described Nixon’s education platform as “part of a larger story about the shift to the left in the party.”

But Cuomo has shifted, too. The question is whether it’s enough, in this overwhelmingly Democratic state, to neutralize Nixon on her signature issue. He’s mostly made peace with the teachers union leadership, for instance, but what about the rank and file? Can Nixon persuade teachers and parents that “Cuomo is a little more like Betsy DeVos than we like to think,” as she said on The Viewlast year? Will New Yorkers buy her argument that the main problem with public schools is that they don’t get enough money?

How Nixon performs in the Democratic primary in September will speak volumes about just how far left the party is willing to go on education; regardless of the outcome, it’s sure to influence the education debate among Democrats who are weighing a presidential run—including Cuomo himself.

From the moment she announced her candidacy, Cynthia Nixon has emphasized that she’s “a proud public school graduate, and a prouder public school parent.” She met Danny Mozes, her first romantic partner and the father of her two eldest children, while attending Manhattan’s Hunter College High School in the early 1980s. Mozes grew up to be a high school English teacher, and Nixon began her education activism around 2001, when their daughter entered kindergarten. It was “kind of her gateway” into politics, as Nixon’s Sex and the City co-star Sarah Jessica Parker told the Times in 2013. She was even arrested at a City Hall protest.

While working with the Alliance, Nixon also met her future wife, Christine Marinoni, who was a director for the group. The pair became key political allies of future mayor Bill de Blasio, and Marinoni later worked in de Blasio’s Department of Education before resigning ahead of Nixon’s campaign. Fellow activists were impressed with Nixon’s commitment, saying she’d show up even when the press didn’t. “I’ve been on buses to Albany with her,” Leonie Haimson, executive director of the advocacy group Class Size Matters, told me. “That’s about the least glamorous thing you could ever do—get up at the crack of dawn and get on a bus to Albany.”

Nixon’s focus has always been on increasing school funding to achieve equity for marginalized students. But Cuomo has argued that simply spending more isn’t enough. “We spend more money per student than any state in the United States,” he said in 2015, according to Politico. “We are decidedly in the middle of the pack in terms of results.... The answer to education has always been the same: More money, more money, more money. We have [that], and you know what it’s gotten us? A larger and larger bureaucracy and higher salaries for people who work in the education industry.”

In his first five years in office, Cuomo aligned himself with the centrist, bipartisan education reform movement. He spearheaded the creation of new teacher evaluations allowing half of a teacher’s rating to be based on students’ standardized test scores. He earned national recognition for championing charters, arguing that competition in the public school system would help “break what is in essence one of the only remaining public monopolies,” as he told The New York Daily Newsin 2014. In many respects, he was part of a national trend.

“What we saw for much of the Obama era was the centrist Democrats—the venture-capital, charter-school supporter wing—really move to prominence,” Hess, of the American Enterprise Institute, told me. “Cuomo was very much of that wing on the party.”

In some ways, he still is, leaving him vulnerable to attacks from the left. Nixon has criticized Cuomo for continuing to support charters, saying they divert money from the traditional public system; accused him of underfunding New York’s neediest schools; charged him with putting public higher education “on a starvation diet”; and called for the immediate repeal of an unpopular law that ties teacher evaluations to students’ standardized test scores—a move that, according to Chalkbeat, “puts Nixon on board with the state’s teachers union agenda and threatens to drive a wedge between Cuomo and the major labor group.”

Yet it’s unclear how worried the governor should be. After years of conflict, he’s made amends with the union. He unveiled his pathbreaking “free college” program with Senator Bernie Sanders last year. And in his State of the State speech in January, he promised a “historic investment in school education.” (Andy Pallotta, president of the New York State United Teachers, said he was “thrilled” by the address.) Even on teacher evaluations, which Cuomo backed three years ago, he’s talking with unions and lawmakers behind the scenes about a possible overhaul.

“In some ways, Cuomo’s position tracks the national conversation,” said David C. Bloomfield, an education professor at Brooklyn College and The CUNY Graduate Center. “He came in, and accountability was at a high-water mark, so he supported charters and test-based accountability. As support for those policies waned across the country and across the state ... he shifted his rhetoric, at least, and downplayed the policies.”

In doing so, he’s given Nixon fewer easy targets for attack. But if her own rhetoric is any indication, there’s one education issue where she thinks she can really hurt him: school funding.

This year, Cuomo increased education funding in the state: He asked for an extra $769 million, and the New York legislature gave him $1.1 billion instead. But the governor also asked for more transparency from cities and towns on how they’re spending the funds. “I’m not going to give any local government one dollar until we know where the money goes, and we make sure the poor schools are getting what they deserve,” he said in a speech at God’s Battalion of Prayer Church in Brooklyn this March.

At an Albany press conference later that month, Nixon called his focus on transparency a “classic stall tactic,” and said, “Cuomo’s entire argument on school funding is just one big excuse to ignore the lives of students who are black or brown or working-class.” (She and the Alliance for Quality Education believe the state owes its schools billions of dollars under a lawsuit settled in 2006.)

Cuomo’s campaign spokesperson, Abbey Fashouer, counters that he “has made education equity a central focus of his tenure, investing a record $27 billion with a focus on our neediest schools, while demanding accountability measures so that the door to opportunity is open for every child—regardless of income, zip code or ethnicity. The governor has worked every day to improve schools across the state through not words, but action.”

That’s a not-so-subtle dig at Nixon’s campaign strategy thus far: She paints Cuomo as a fair-weather progressive, pointing to past positions that he’s since disavowed or avoided, but she hasn’t offered a comprehensive policy agenda of her own. (Nixon’s campaign says her education platform is forthcoming.) Even still, her entry into the race has clearly rattled Cuomo, nudging him left on a number of issues, and she’s chipping away at his lead: The latest Quinnipiac polling shows him ahead by 22 points, down from 30 or 40 in earlier polls.

Beyond New York, Nixon’s campaign raises pressing questions for Democrats as they aim to retake at least half of Congress this fall and the White House in 2020. Will they really abandon charter schools en masse, even as liberal policy shops like the Center for American Progress keep making the case for them? Are they agreed that increased funding for schools is the top issue in American education? And exactly how much of Obama’s legacy will they “bury in the basement”?

Nixon won’t have to answer these questions herself, unless she pulls off a historic upset. But Cuomo will—if not this year, then on abigger campaign trailto come.